diff --git a/kitty/layout/base.py b/kitty/layout/base.py
index acb30de4b..ed4b65562 100644
--- a/kitty/layout/base.py
+++ b/kitty/layout/base.py
@@ -445,9 +445,7 @@ def serialize(self, all_windows: WindowList) -> dict[str, Any]:
         ans = self.layout_state()
         ans['opts'] = self.layout_opts.serialized()
         ans['class'] = self.__class__.__name__
-        ans['all_windows'] = aw = all_windows.serialize_state()
-        for wg in aw['window_groups']:
-            wg['window_ids'] = tuple(w['id'] for w in aw.pop('windows'))
+        ans['all_windows'] = all_windows.serialize_layout_state()
         return ans
 
     def unserialize(
diff --git a/kitty/window_list.py b/kitty/window_list.py
index 6c01829ca..0fba377c1 100644
--- a/kitty/window_list.py
+++ b/kitty/window_list.py
@@ -96,7 +96,13 @@ def remove_window(self, window: WindowType) -> None:
     def serialize_state(self) -> dict[str, Any]:
         return {
             'id': self.id,
-            'windows': [w.serialize_state() for w in self.windows]
+            'windows': tuple(w.serialize_state() for w in self.windows),
+        }
+
+    def serialize_layout_state(self) -> dict[str, Any]:
+        return {
+            'id': self.id,
+            'window_ids': tuple(w.id for w in self.windows),
         }
 
     def unserialize_layout_state(self, window_ids: Sequence[int]) -> None:
@@ -185,6 +191,13 @@ def serialize_state(self) -> dict[str, Any]:
             'window_groups': [g.serialize_state() for g in self.groups]
         }
 
+    def serialize_layout_state(self) -> dict[str, Any]:
+        return {
+            'active_group_idx': self.active_group_idx,
+            'active_group_history': list(self.active_group_history),
+            'window_groups': [g.serialize_layout_state() for g in self.groups]
+        }
+
     def unserialize_layout_state(self, state: dict[str, Any], window_id_map: dict[int, int]) -> dict[int, int] | None:
         if set(window_id_map.values()) != set(self.id_map):
             # some window in this collection does not correspond to a